Recently, a transformer has become an essential magnetic element for regulating voltage into required voltages for various kinds of electric appliances.
FIG. 1 is a schematic perspective view illustrating a conventional transformer. As shown in FIG. 1, the transformer 1 comprises a bobbin 10, a primary coil (not shown), a secondary coil (not shown) and a magnetic core assembly 11. The primary coil and the secondary coil are separately wound on the bobbin 10. In addition, an insulating tape 12 is wound on the primary coil and the secondary coil. The terminals 131 of the primary coil are wound and fixed on corresponding pins 101 of the bobbin 10. In addition, the first terminals 131 of the primary coil are sheathed by corresponding tubes 132. The terminals 141 of the secondary coil are sheathed by corresponding tubes 142 and used as fly wires. The magnetic core assembly 11 is partially accommodated within a channel (not shown) of the bobbin 10. Plural layers of insulating tapes 12 are wound on the magnetic core assembly 11 in order to comply with the safety requirements. The transformer 1 can be electrically connected with a circuit board through the pins 101 and the terminals 141 of the secondary coil.
The conventional transformer 1, however, still has some drawbacks. For example, during operation of the transformer 1, the temperatures of the primary coil, the secondary coil and the magnetic core assembly 11 will be largely increased. Since the insulating tapes 12 are wound on the magnetic core assembly 11, the heat generated by the transformer 1 is difficult to be dissipated away. If a large amount of heat is accumulated within the transformer 1, the operating performance and electrical safety of the power circuit having the transformer 1 will be deteriorated.